The difference between the application of colorimeter and sp
[Abstract] How to establish color standards, improve product appearance, color quality control, and then computer color matching? Here we have to mention a color detection tool - colorimeter. And now, the color meter...
How to establish color standards, improve product appearance, color quality control, and then computer color matching? Here we have to mention a color detection tool - colorimeter.
At present, there are many types of color measuring instruments, brands, and merchants. Some customers do not know much about color measurement. In the face of all kinds of instruments, there will be a large price gap, and the measurement results are different. Why is it called a colorimeter, and some is a spectrophotometer? What are the differences between these instruments and what are they applied to?
Here we will give a detailed introduction:
1, what is called "color difference meter", what is called "spectrophotometer"
The "color difference meter" as the name suggests is used to measure the color difference between two samples. The accuracy is relatively low, and generally the absolute value (L, a, b value) of the color coordinate space of the color cannot be accurately given, but the color difference between the two samples (usually between the standard and the sample) can be given ( ΔE), this colorimeter has no absolute data of color, there is no way to exchange data with others, nor can it establish and manage its own color standard database.
The spectrophotometer has high precision and uses the setting of the pre-positioning board, which eliminates the need to use the standard blackboard and whiteboard during the calibration of the traditional colorimeter and color difference meter. The built-in software is powerful, with all the necessary color equations, standard light sources for different tasks, and a wide range of industry-specific and application-specific metrics.
2, the design principle
The spectrophotometer is designed according to the principle of spectroscopic type, and the ordinary colorimeter is designed according to the principle of tristimulus value. The color separation colorimeter has high precision and increasing versatility. The color spectrum spectrophotometer can simultaneously measure SCI (a method that includes specular reflection for measurement. For this reason, it minimizes the effects of the sample surface, especially for color quality monitoring and computer color matching) and SCE (is A method of measuring specular reflections. The results of this type of measurement are similar to those observed by the naked eye. Since it can measure the reflectance at each wavelength, it is suitable for complex color analysis, and of course the price is relatively expensive. The tristimulus colorimeter has the characteristics of relatively low price, small size, superior flexibility and easy operation.
3, the principle of measurement
The color difference meter can automatically compare the color difference between the sample and the tested product, and output four sets of color difference data of CIE L, a, b and colorimetric △E, △L, △a, △b. Unlike the method of color measurement by a simple colorimeter, the spectrophotometer can measure the "reflectance curve" of each color point (10 nm or 20 nm wavelength interval), while the color difference meter cannot. A spectrophotometer can simulate a variety of light sources, while a colorimeter typically has only one or a maximum of two analog sources.
4, the light source
In a color measuring instrument, the choice of which source should be considered first is stability, source orientation, lifetime, and the effectiveness of the resulting spectral curve. At present, most of the light sources are LED lamps and xenon lamps.
Xenon lamps are generally used for ultraviolet light source measurement, and can emit short-term high-intensity arcs, but it is difficult to generate repeated equal-intensity arcs. In addition, the xenon lamp source requires a relatively complicated high-voltage oscillation excitation circuit, and the maintenance is also very complicated. When replacing, in addition to replacing the bulb, the entire set of capacitors must be replaced, so the price is relatively expensive.
In current standard color measuring instruments, the use of LED lights is technically and economically suitable. In particular, portable instruments need to be lightweight, power efficient, and easy to maintain and operate. Color spectrum color measuring instruments use long-life CLEDs (full-band balanced Led light source), which does not have to worry about the need to replace the light source frequently.